Need to cancel a rejected credit memo from Projects

I'd appreciate any help I can get with this issue:

Draft invoice 1 was created in Projects, was interfaced and had cash applied.  On the same day, the functional user created a credit memo to cancel draft invoice 1 and it is in rejected status in Autoinvoice because of the cash application.  (I know what you are thinking, but no, I don't know why, and she is now retired, so I don't know her thought process.)

Errors: 1) The total amount of your credit memo cannot exceed the balance of the debit item it is crediting

            2) You cannot apply a transaction with a negative amount to another transaction with a negative balance and vice versa